fix: update new channel icon color on chat main modal (#521)

## Description
his PR includes a fix to update the new channel item’s icon on the chat
main modal.

## Additional Notes
N/A

## Type of Change
- [x] Bug fix
- [ ] New feature
- [ ] Breaking change
- [ ] Refactoring
- [ ] Documentation
- [ ] Chore

## Screenshots (if applicable)
<!-- Include screenshots to demonstrate any UI changes. -->

<img width="180" alt="image"
src="https://github.com/user-attachments/assets/29c47986-78a1-467b-b3f1-3a0cc7eccf29">

lib/app/features/chat/model/conversation_type.dart

@@ -43,7 +43,7 @@ enum ConversationType implements MainModalListItem {
     return switch (this) {
       ConversationType.private => Assets.svg.iconChatCreatenew,
       ConversationType.group => Assets.svg.iconSearchGroups,
-      ConversationType.channel => Assets.svg.iconFeedArticles,
+      ConversationType.channel => Assets.svg.iconSearchChannel,
     };
   }
 }